This invention generally relates to scroll compressors, and more particularly to an air cooling system for scroll air compressors and other related rotary machines.
In scroll air compressor design, a critical concern is to maximize heat dissipation from the compressor. As more heat is dissipated from a scroll air compressor, operating life is extended for such assemblies as bearings and tip seals. Also, a scroll air compressor can be operated effectively at higher pressures if heat dissipation is maximized.
Generally, a counter flow type heat exchanger is more efficient than a parallel flow type heat exchanger. However, typical scroll air compressor cooling systems do not employ a counter flow type heat exchanger. Conventional scroll air compressor designs incorporate a cooling air flow which requires cooling air to flow completely across the back of the orbiting and/or fixed scroll assemblies. This is accomplished through use of a plurality of ribs or fins which are arranged in rows on the back portions of both the orbiting and fixed scrolls.
In the operation of such conventional scroll compressors, cooling air flows from a location at the perimeter of the fixed and/or orbiting scrolls toward the center of the scrolls. As is well known in the art, the temperature is the greatest at this central portion of the scrolls. From the central portion of the scrolls, the cooling air, which at this time is sufficiently heated, flows outwardly across the remainder of the scroll body. As may be appreciated by one skilled in the art, with this type cooling flow, the capacity for the heated cooling air to dissipate heat is limited. Also, the heated cooling fluid may put heat back into the scroll compressor as it flows across the remainder of the scroll.
The foregoing illustrates limitations known to exist in present cooling systems for scroll air compressors. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.